dna_to_rna_to_amino_acid_name.py

import string


dna_letters = "ATGC" #All possible DNA letter
rna_letters = "UACG" #All possible RNA Letters

dna = input("Please enter you DNA string: ") #Gets DNA Input
dna = dna.upper()  #Changes DNA to uppercase if not already
print(f"Your DNA sequence is: {dna}") #Prints the DNA Sequence

rna = "" #Creates a blank variable

for letter in dna: #For ever letter in DNA it loops
    for i in range(4): #Loops 4 times since there is only 4 possible letters
        if letter == dna_letters[i]: #If hat index is the same as one of the letters
            rna += rna_letters[i] #Adds the RNA version of it to the variable


print(f"Your messenger RNA strand is: {rna}") #Prints the Final RNA sequence

rna_codon_3_letter = {"UUU":"Phe", "UCU":"Ser", "UAU":"Tyr", "UGU":"Cys", "UUC":"Phe", "UCC":"Ser", "UAC":"Tyr", "UGC":"Cys", "UUA":"Leu", "UCA":"Ser", "UAA":"STO", "UGA":"STO", "UUG":"Leu", "UCG":"Ser", "UAG":"STO", "UGG":"Trp", "CUU":"Leu", "CCU":"Pro", "CAU":"His", "CGU":"Arg", "CUC":"Leu", "CCC":"Pro", "CAC":"His", "CGC":"Arg", "CUA":"Leu", "CCA":"Pro", "CAA":"Gln", "CGA":"Arg", "CUG":"Leu", "CCG":"Pro", "CAG":"Gln", "CGG":"Arg", "AUU":"Ile", "ACU":"Thr", "AAU":"Asn", "AGU":"Ser", "AUC":"Ile", "ACC":"Thr", "AAC":"Asn", "AGC":"Ser", "AUA":"Ile", "ACA":"Thr", "AAA":"Lys", "AGA":"Arg", "AUG":"Met", "ACG":"Thr", "AAG":"Lys", "AGG":"Arg", "GUU":"Val", "GCU":"Ala", "GAU":"Asp", "GGU":"Gly", "GUC":"Val", "GCC":"Ala", "GAC":"Asp", "GGC":"Gly", "GUA":"Val", "GCA":"Ala", "GAA":"Glu", "GGA":"Gly", "GUG":"Val", "GCG":"Ala", "GAG":"Glu", "GGG":"Gly"}

amino_acid = ""
for i in range(0, len(rna)-(3+len(rna)%3), 3):
    if rna_codon_3_letter[rna[i:i+3]] == "STOP" :
        break
    amino_acid += rna_codon_3_letter[rna[i:i+3]]
    amino_acid += " "

amino_acid += rna_codon_3_letter[rna[-3:]]



print(f"Your amino aicd chain is: {amino_acid}")